The present invention relates to powered applicators such as drenchers, vaccinators, injectors and other fluid dispensing devices, typically used to dispense fluid products such as medicaments and pharmaceuticals to animals,
Dispensing of fluid (usually liquid) products (specifically medicaments and pharmaceutical products) has traditionally been achieved utilizing manually powered applicators such as drenchers, vaccinators, injectors and other manual fluid dispensing devices. The limitations of these devices have been the hand pressure required to continually operate such a manual system and the related fatigue and RSI problems resulting from mass usage.
A portable hand held, powered system would alleviate these problems as it would mean that the user would simply need to manually or mechanically press a button or switch which in turn would activate the device delivering the required action under power.
Hand held, portable powered systems currently in use in the pharmaceutical and affiliated fluid dispensing fields are predominantly powered by either compressed air or Liquid Petroleum Gas (LPG). These systems are useful but have limitations in areas/locations where compressed air or high pressure LPG is not readily available. In addition, the most commonly used portable hand held systems in these industries are operated with LPG which can be hazardous when used in confined spaces due to the exhausting of gas into the atmosphere.
It is the object of the present invention to overcome or substantially ameliorate the above disadvantage.
There is disclosed herein a powered injector to deliver a liquid, said injector including:
a body;
a cylinder in the body;
a piston slidably mounted within the cylinder so as to cooperate therewith to enclose a variable volume chamber;
an outlet extending from said chamber and being adapted to receive a needle through which the liquid is delivered;
a needle shroud movably mounted on the body so as to be movable between an extended position at which the needle would be covered by the shroud, and a retracted position at which the needle is exposed;
an inlet extending to said chamber to deliver liquid thereto;
a solenoid mounted in the body and having a movable actuator connected to the piston, said actuator being caused to move generally linearly from a first position to a second position upon the solenoid being energised, with said piston being caused to reduce die volume of said chamber when said actuator moves from said first position to said second position;
an electric switch connected to said solenoid to deliver electric power thereto to energise said solenoids the switch being mounted on said body so as to be engaged by said shroud when moved to the retracted position thereof; and wherein
when said shroud moves to said extended position said electric switch disconnects said solenoid from electric power so that said actuator moves from said second position to said first position causing said piston to increase the volume of said chamber and draw liquid into said chamber via said inlet.
Preferably, said injector includes a spring urging said piston to increase the volume of said chamber.
Preferably, the injector includes a one-way valve in said inlet restricting fluid to flow toward said chamber, and a valve in said outlet restricting fluid to flow toward said needle.
Preferably, said inlet includes a passage extending through said piston and a flexible conduit extending to said passage.
Preferably, a spring urges said shroud to said extended position.
Preferably, said device includes a battery connected to said switch and solenoid.